28
Q:

# A watch which gains uniformly is 2 minutes low at noon on monday and is 4 min.48 sec fast at 2 p.m on the following monday. when was it correct ?

 A) 2 p.m on Tuesday B) 2 p.m on Wednesday C) 3 p.m on Thursday D) 1 p.m on Friday

Answer:   B) 2 p.m on Wednesday

Explanation:

Time from 12 p.m on monday to 2 p.m on the following monday = 7 days 2 hours = 170 hours

$\therefore$ The watch gains $\inline&space;\left&space;(&space;2+4\frac{4}{5}&space;\right&space;)$ min. or  $\inline&space;\frac{34}{5}$ min. in 170 hrs.

Now, $\inline&space;\frac{34}{5}$ min. are gained in 170 hrs.

$\inline&space;\therefore$ 2 min are gained in $\inline&space;\left&space;(&space;170\times&space;\frac{5}{34}\times&space;2&space;\right&space;)$ hrs = 50 hrs

$\inline&space;\therefore$ Watch is correct 2 days 2 hrs. after 12 p.m on monday i.e it will be correct at  2 p.m on wednesday.

Q:

A watch gains 5 seconds in 3 minutes and was set right at 8 AM. What time will it show at 10 PM on the same day ?

 A) 10 : 27 : 41 AM B) 8 : 51 : 04 AM C) 9 : 45 : 15 PM D) 10 : 23 : 20 PM

Answer & Explanation Answer: D) 10 : 23 : 20 PM

Explanation:

The watch gains 5 seconds in 3 minutes = 100 seconds in 1 hour.

From 8 AM to 10 PM on the same day, time passed is 14 hours.

In 14 hours, the watch would have gained 1400 seconds or 23 minutes 20 seconds.

So, when the correct time is 10 PM, the watch would show 10 : 23 : 20 PM

2 30
Q:

How many degrees will the minute hand move, in the same time in which the second hand move 5400 ?

 A) 90 degrees B) 85 degrees C) 60 degrees D) 45 degrees

Answer & Explanation Answer: A) 90 degrees

Explanation:

Minute hand covers 5400/60 = 90°

2 12
Q:

In 16 minutes, the minute hand gains over the hour hand by -

 A) 16 deg B) 80 deg C) 88 deg D) 94 deg

Answer & Explanation Answer: C) 88 deg

Explanation:

In one hour, the minute hand gains 330° over the hour hand. i.e., 60 minute, the minute hand gains 330° over the hour hand.

∴ In 16 minutes, the minute hand gain over the hour hand by

3 42
Q:

At 6′o clock a clock ticks 6 times. The time between first and last ticks is 30 seconds. How long does it tick at 12′o clock ?

 A) 66 sec B) 55 sec C) 36 sec D) 24 sec

Answer & Explanation Answer: A) 66 sec

Explanation:

For ticking 6 times, there are 5 intervals.

Each interval has time duration of 30/5 = 6 secs

At 12 o'clock, there are 11 intervals,
so total time for 11 intervals = 11 x 6 = 66 secs.

4 199
Q:

At what time between 3 and 4 o’clock will the minute hand and the hour hand are on the same straight line but facing opposite directions ?

 A) 3:15 2/8 B) 3:49 C) 3:49 1/11 D) 3:51

Answer & Explanation Answer: C) 3:49 1/11

Explanation:

On straight line means 180 degree angle.
180 = 11/2 min – 30 hrs
180 = 11/2 m – 30 × 3
180 = 11/2 m – 90
(180 + 90) 2 = 11 m
m = 540/11 = 49 1/11 minutes.

$\inline \fn_jvn \therefore time = 3: 49 \frac{1}{11}$